weird fish behaviour

Question
QUESTION: Hi jon,
one day i went to feed my fish as usual and i discovered that one of the goldfish was lying on its side at the bottom of the pond. we have a large ceramic outdoor fish pond which allows a number of predators to terrorise the fish. i have often seen the cats slap at the water when the fish are swimming at the top. the fish of concern is also swimming upside down and randomly sinking to the bottom at times and not moving. i have noted that there seems to be a puncture wound on the side of its head could this have been caused by the cats? does it have concussion? the other fish seem normal. I am very concerned please help!!!

ANSWER: Hello Rina, a few questions for you to start with. What kind of temperatures are you dealing with where you are, how big are the goldfish, and how long have you had them. What TYPE of goldfish are they and Was there any other signs of a predator attack in the pond.

A lot of these things play a big factor in the health and life span of these fish. You mentioned you have cats which were slapping the water at the fish. It is possible your fish could have a wound from a predator, whether its your cat or not. Direct sunlight, here in Florida of the United States, would pretty much almost boil pond fish if there is no cover for them. Doesn't seem you have this issue though, just be aware. One thing that catches my attention is you say it has a wound on the side of its head. I'm not sure if you have heard of "HOLE IN THE HEAD" disease. Properly known as, "HEAD AND LATERAL LINE EROSION"". This is a very misunderstood disease and little research has been done to find out the exact cause of this. Whether or not this is what your fish has or if it is in fact a puncture wound from some sort of predator, or some other internal parasitic disease, this "hole" or "wound", makes your fish highly susceptible to catching other diseases. Although hole in the head disease doesn't necessarily incapacitate your fish that quickly in comparison to your explanation of yours, unless it is very severe of course and there are numerous holes and so forth. Normally there are MANY holes, and it occurs mainly in the "cichlid" group of fish. Either way, I would remove it from the others and put it in a hospital tank and monitor its behavior while administering medications and such to aid in its recovery, if you think you would be better off trying that rather than purchasing a new one. I hope this helps you. Please feel free to ask anymore questions if you need to. Good Luck.

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QUESTION: wow i didn't know the world of fish could be so complicated
Australian sunlight is also very harsh but you're right about it probably not being the problem, the fish pond is underneath the back verandah which is sheilded by a growth of climbing vines. i have recently cleaned out the pond, which i guiltly admit has not been changed for a while. (too busy in my last year of school!!)could the filthy water play a role? as for other predators there are many birds which also terrorise the fish however they are easily scared off and dont really get the chance to harm the fish. there didnt seem to be any other signs of a predator attack in the pond. the goldfish we have are just ordinary goldfish, im not quite sure of the specific type.the weird behaving one is larger and pure gold and the other is gold and cream. i have had the fish for about a year, we originally started off with three fish but one died mysteriously without the precence of a wound. i love animals and i dont want to just replace it so what medication were you  suggesting?  

Answer
Hey there, well as we all know, any outdoor pond that holds fish is en easy target for predators. About the first fish which mysteriously died, that could've been just from stress alone. One of the most common causes of fish deaths is stress. Almost anything can stress a fish out, especially when it is first placed in a new environment. Once it gets used to its new surroundings, the chance of that slims down some. As for your goldfish that is presently injured, I like to purchase medications of the "Maracyn" brand. These have always prevailed for me. There are many different kinds of medications for a variety of diseases, including bacterial diseases, and also internal and external parasites. I'm not sure of the franchises of pet stores in your area but I'm sure whatever you have will have medications. Buy a medication which will aid in the repair of damaged  fins and replaces slime coating such as stress coat, which should and can be added each time you clean the pond and or replace the water, which by the way should be done at least monthly. Goldfish are very dirty fish. Not a top choice of mine, but they are pretty. Dirty water carries all sorts of harmful toxins which could make them sick and most definitely turn fatal. Also, the Maracyn medicines are used to treat bacterial and parasitic infestations. But, if you can get the fish removed and into a hospital tank, u may or may not have these secondary problems. As I mentioned before, feel free to ask more questions if need be. I hope you find this helpful. Again, good luck.